Whilst all your enthusiasm for GrapheneOS and potential new features is appreciated, this thread appears to have morphed into some of you posting long lists of all the features which you are looking for, which I don't believe is quite what the OP intended. The original question was about which feature users would like to see implemented next.
Many of the features requested have their own issues on GitHub, so you can track their process there: https://github.com/GrapheneOS/os-issue-tracker/issues.
Some of the other features requested are already possible, and there are others that seem to misunderstand how GrapheneOS and Android more generally works.
For me to reply to each comment individually would cause this thread to become too cumbersome so I would encourage you to please refer to the issue tracker on GitHub: https://github.com/GrapheneOS/os-issue-tracker/issues.
If you can't find a relevant issue listed there or would like to discuss a more general idea, then I'd encourage you to open a new thread on this forum.